Metal-organic frameworks and covalent organic frameworks as disruptive membrane materials for energy-efficient gas separation.

In this Review we survey the molecular sieving behaviour of metal-organic framework (MOF) and covalent organic framework (COF) membranes, which is different from that of classical zeolite membranes. The nature of MOFs as inorganic-organic hybrid materials and COFs as purely organic materials is powerful and disruptive for the field of gas separation membranes. The possibility of growing neat MOFs and COFs on membrane supports, while also allowing successful blending into polymer-filler composites, has a huge advantage over classical zeolite molecular sieves. MOFs and COFs allow synthetic access to more than 100,000 different structures and tailor-made molecular gates. Additionally, soft evacuation below 100 °C is often enough to achieve pore activation. Therefore, a huge number of synthetic methods for supported MOF and COF membrane thin films, such as solvothermal synthesis, seed-mediated growth and counterdiffusion, exist. Among them, methods with high scale-up potential, for example, layer-by-layer dip- and spray-coating, chemical and physical vapour deposition, and electrochemical methods. Additionally, physical methods have been developed that involve external stimuli, such as electric fields and light. A particularly important point is their ability to react to stimuli, which has allowed the 'drawbacks' of the non-ideality of the molecular sieving properties to be exploited in a completely novel research direction. Controllable gas transport through membrane films is a next-level property of MOFs and COFs, leading towards adaptive process deviation. MOF and COF particles are highly compatible with polymers, which allows for mixed-matrix membranes. However, these membranes are not simple MOF-polymer blends, as they require improved polymer-filler interactions, such as cross-linking or surface functionalization.

Measurement of canine Th17 cells by flow cytometry.

Th17 cells are T helper cells which play an important role during inflammation and autoimmune disease. To investigate the role of these cells in diseases in dogs in a clinical setting, methods for fast identification had to be established. Th17 cells are a rare cell population, for their measurement stimulation is recommended. To examine more samples simultaneously and to receive a relatively high purity of cell population of CD3 + CD4+ cells, different methods on various levels of preselection of cells as well as the possibility of storing blood overnight for measuring Th17 cells by flow cytometry were investigated. Firstly, to receive a high number of mononuclear cells, two different density gradients were compared and analysed. Furthermore, the enrichment of CD3 + CD4+ cells via depletion of CD8alpha+, CD11b + and CD21+ cells by cell sorting (autoMACS Pro Separator) was tested. It was also investigated whether stimulation processes led to better interpretation of results and whether there was a significant difference in measurement of directly processed blood samples and samples that had been stored overnight. In conclusion, the use of the density gradient (Lymph24+ Spin Medium) resulted in a purer cell population through a significant decrease in polymorphonuclear cells (*p = 0.01). After cell sorting, a significant difference in cell population purity was detected. Within the target fraction (containing mainly CD3 + CD4+ cells), CD8alpha+, CD21+, CD11b + cell percentages were significantly lower (***p < 0.001, *p < 0.02, ***p < .0001, respectively), and CD3 + CD4+ cell percentage was significantly higher (***p < .0001). There was a significant difference in Th17 cell percentage between unstimulated and stimulated cell populations (***p < .0001), but no significant difference in the percentage of unstimulated Th17 cells (p = 0.29) or stimulated Th17 cells (p = 0.71) in stored blood in comparison to directly processed EDTA blood samples. Finally, a modified protocol that offers an efficient way to investigate samples that were stored overnight by means of flow cytometry was evolved to research the role of Th17 cells in dogs with different diseases or in healthy populations.

Defibrillation of soft porous metal-organic frameworks with electric fields.

Gas transport through metal-organic framework membranes (MOFs) was switched in situ by applying an external electric field (E-field). The switching of gas permeation upon E-field polarization could be explained by the structural transformation of the zeolitic imidazolate framework ZIF-8 into polymorphs with more rigid lattices. Permeation measurements under a direct-current E-field poling of 500 volts per millimeter showed reversibly controlled switching of the ZIF-8 into polar polymorphs, which was confirmed by x-ray diffraction and ab initio calculations. The stiffening of the lattice causes a reduction in gas transport through the membrane and sharpens the molecular sieving capability. Dielectric spectroscopy, polarization, and deuterium nuclear magnetic resonance studies revealed low-frequency resonances of ZIF-8 that we attribute to lattice flexibility and linker movement. Upon E-field polarization, we observed a defibrillation of the different lattice motions.

Mass medical care with scarce resources: the essentials

This guide from Department of Health & Human Services' (HHS) Agency for Healthcare Research and Quality (AHRQ) can help community planners prepare for public health emergencies, such as pandemic flu, when demand for medical resources outweighs supply. The guide includes information on ethical and legal issues, and on the provision of services to address pre-hospital, acute hospital care, alternative care sites, and palliative care during a public health emergency.

JNK phosphorylates Yes-associated protein (YAP) to regulate apoptosis.

Yes-associated protein (YAP) regulates DNA damage and chemosensitivity, as well as functioning as a pro-growth, cell size regulator. For both of its roles, regulation by phosphorylation is crucial. We undertook an in vitro screen to identify novel YAP kinases to discover new signaling pathways to better understand YAP's function. We identified JNK1 and JNK2 as robust YAP kinases, as well as mapped multiple sites of phosphorylation. Using inhibitors and siRNA, we showed that JNK specifically phosphorylates endogenous YAP in a number of cell types. We show that YAP protects keratinocytes from UV irradiation but promotes UV-induced apoptosis in a squamous cell carcinoma. We defined the mechanism for this dual role to be YAP's ability to bind and stabilize the pro-proliferative ΔNp63α isoform in a JNK-dependent manner. Our report indicates that an evaluation of the expression of the different isoforms of p63 and p73 is crucial in determining YAP's function.

[Screening for depersonalization-derealization with two items of the cambridge depersonalization scale]. / Screening nach Depersonalisation-Derealisation mittels zweier Items der Cambridge Depersonalisation Scale.

Depersonalization (DP) and derealization (DR) are considered to be highly underdiagnosed. Therefore the development of screening instruments is important. From the Cambridge Depersonalization Scale (CDS) two items were extracted discriminating best patients with clinical significant DP from patients without DP. These two Items were assembled to a short version of the CDS. This short version (CDS-2) was tested in a sample of 38 patients with clinical significant DP-DR and 49 patients without or only mild DP-DR. Scores were compared against clinical diagnoses based on a structured interview (gold standard). The CDS-2 was able to differentiate patients with clinical significant DP well from other groups (cut-off of CDS-2>or=3, sensitivity=78.9%, specifity=85.7%) and also showed high reliability (Cronbachs alpha=0.92). Therefore the CDS-2 can be considered as a useful tool for screening and identification of DP-DR.

A novel method to identify protein kinase substrates: eEF2 kinase is phosphorylated and inhibited by SAPK4/p38delta.

We have developed a method of general application for identifying putative substrates of protein kinases in cell extracts. Using this procedure, we identified the physiological substrates of several mitogen-activated protein kinase kinases and an authentic substrate of stress-activated protein kinase (SAPK) 2a/p38. A 120 kDa protein was detected in skeletal muscle extracts that was phosphorylated rapidly by SAPK4/p38delta, but poorly by SAPK2/p38, SAPK3/p38gamma, SAPK1/JNK or extracellular signal-regulated kinase 2 (ERK2). It was purified and identified as eukaryotic elongation factor 2 kinase (eEF2K). SAPK4/p38delta phosphorylated eEF2K at Ser359 in vitro, causing its inactivation. eEF2K became phosphorylated at Ser359 and its substrate eEF2 became dephosphorylated (activated) when KB cells were exposed to anisomycin, an agonist that activates all SAPKs, including SAPK4/p38delta. The anisomycin-induced phosphorylation of Ser359 was unaffected by SB 203580, U0126 or rapamycin, and was prevented by overexpression of a catalytically inactive SAPK4/p38delta mutant, suggesting that SAPK4/p38delta may mediate the inhibition of eEF2K by this stress. The phosphorylation of eEF2K at Ser359 was also induced by insulin-like growth factor-1. However, this was blocked by rapamycin, indicating that Ser359 is targeted by at least two signalling pathways.

Dyspnea management in alpha-1 antitrypsin deficiency: effect of oxygen administration.

BACKGROUND: A deficiency of alpha-1 antitrypsin (AAT) can lead to pulmonary disease in middle-aged adults in whom dyspnea management can be a significant issue. OBJECTIVE: The research addressed whether short-term oxygen (O2) administration during activities might decrease dyspnea and improve exercise performance in nonhypoxemic patients with emphysema caused by a deficiency of alpha-1 antitrypsin. METHOD: This was a double-blind, randomized crossover study of 31 subjects with a deficiency of AAT (mean + SD, age = 47 +/- 7), moderate emphysema and a resting PaO2 > 70 mm Hg. Oxygen saturation (SpO2), 6-minute walk distance, and end of walk dyspnea were measured during three practice walks and during walks with nasal cannula administration of O2 (intervention) and compressed air (control). RESULTS: Repeated measures analysis of variance (ANOVA) showed significant differences across the walks for SpO (F= 18.9, p = 0.0001), 6-minute walk distance (F= 6.07, p = 0.004), and dyspnea (F= 4.44, p = 0.016). Using post hoc contrasts, SpO2 was the only variable that differed between 20, and compressed air (p < 0.0001). There was, however, an interaction effect of gender with O2 for dyspnea (F= 9.85, p = 0.004). Mean values showed that men did not benefit from O2 (p = 0.87). However, women experienced less dyspnea when receiving O2 as compared with compressed air (p = 0.0025), and although not statistically significant, the lower dyspnea with O2 corresponded with an increased walk distance of 79 feet. CONCLUSIONS: O2 administration may be useful for reducing dyspnea during exercise in selected populations.

A pilot study exploring mood state and dyspnea in mechanically ventilated patients.

OBJECTIVE: The objective of this study was to explore preweaning mood state and dyspnea in mechanically ventilated patients. METHODS: Before ventilatory weaning, 21 critically ill patients completed the short profile of mood states (higher scores equal greater disturbance), and a 10 cm dyspnea visual analogue scale (none to extremely severe). Weaning outcome at 24 hours was recorded. RESULTS: The mean +/- SD total mood disturbance (possible range, 0 to 16) and subscale scores (possible range, 0 to 4) were as follows: total, 6.10 +/- 4.06; tension, 1.07 +/- 0.64; depression, 1.16 +/- 0. 93; anger, 1.05 +/- 0.82; vigor, 1.04 +/- 0.84; fatigue, 1.96 +/- 0. 90; and confusion, 1.27 +/- 0.91. Mean dyspnea was 3.22 +/- 2.26 cm. Dyspnea intensity correlated negatively with vigor (r = -0.38, P <. 10). Lower preweaning vigor tended to differentiate successful from unsuccessful weaning (Mann-Whitney U = 22.0; P =.07). CONCLUSION: Patients who weaned successfully experienced greater mood disturbance. Moderate mood disturbance may be a necessary stimulus for successful weaning.

Comparison of different methods of obtaining orthostatic vital signs.

The purpose of this study was to compare two lying and standing procedures for measuring orthostatic vital signs. Thirty-five normotensive participants (mean age 21.6 years)participated in a randomized crossover study. Measures of blood pressure (BP), heart rate, and dizziness were collected at different lying and standing times. AU subjects participated in a standardized walk paced at 4 miles per hour prior to lying. Using analysis of variance (ANOVA) with post hoc contrasts, the mean systolic BP differed between 5 and 10 minutes of lying (F = 21.33, p < .001) and the mean diastolic BP tended to differ between those time points (F = 5.23, p < .03). The mean standing systolic BP and dizziness rating were different between 0- and 2-minute intervals (F = 8.36, p < .01 and F = 7.15, p < .10). In normotensive participants following standardized exercise, orthostatic vital signs stabilized after lying 10 minutes.

Inactivation of protein-tyrosine phosphatases as mechanism of UV-induced signal transduction.

UV irradiation of cells causes ligand-independent activation of receptor tyrosine kinases. On the basis of dephosphorylation kinetics, UV-induced inactivation of receptor-directed tyrosine phosphatases (PTP) has been proposed as the mechanism of receptor activation (Knebel, A., Rahmsdorf, H. J., Ullrich, A., and Herrlich, P. (1996) EMBO J. 15, 5314-5325). Here we show that four defined protein-tyrosine phosphatases (PTPs), SHP-1, RPTPalpha, RPTPsigma, and DEP-1, are partially inactivated upon UV irradiation of PTP-overexpressing cells. The dephosphorylation of coexpressed platelet-derived growth factor beta (PDGFbeta) receptor by RPTPalpha is inhibited upon UV irradiation. UV converts RPTPalpha into a substrate-trapping enzyme which can coprecipitate PDGFbeta receptor, similarly to the PTP mutant at the active-center cysteine: C433S. In agreement with the proposed mechanism that inactivation of PTPs accounts for receptor tyrosine kinase activation, no evidence for a UV-induced receptor cross-linking could be obtained in PDGFbeta receptor-enriched membrane micelle preparations and in PDGFbeta receptor overexpressing 293 cells. The intrinsic activity of PDGFbeta receptor kinase was required for the UV-induced enhancement of receptor phosphorylation, but was not changed upon UV irradiation. The data support a mechanism of UV-induced signal transduction involving inactivation of PTPs through an unknown reactive intermediate that oxidizes the conserved cysteine in the active sites of PTPs.

Health related quality of life and disease severity in patients with alpha-1 antitrypsin deficiency.

STUDY QUESTION: To describe health-related quality of life (HRQL) in individuals with alpha-1 antitrypsin (AAT) deficiency, examine the cross-sectional relationship between disease severity and HRQL, and explore changes in lung function and HRQL over time in a subset of these individuals. MATERIAL/METHODS: Forty-five adults with AAT deficiency and moderate to severe emphysema completed the Chronic Respiratory Disease Questionnaire (CRQ), six-minute walk distance (6-MWD) and pulmonary function tests (PFTs). Twenty of the 45 were followed for two additional years with repeated measurements of CRQ and PFTs. RESULTS: The mean +/- SD age was 49 +/- 8 years. Initial CRQ subscale scores were: dyspnea 17.5 +/- 4.3; fatigue 17.0 +/- 5.46; emotional function 33.1 +/- 8.67; and mastery 21.7 +/- 4.65. No relationship was found between percent predicted forced expiratory volume in one second (FEV1%) and CRQ score; 6 MWD and fatigue correlated significantly (r = 0.32, p < 0.05). Repeated PFT and CRQ measurements in 20 subjects showed statistically significant declines in FEV1 and slow vital capacity (SVC), but no change in CRQ scores. CONCLUSIONS: Results suggest persons with AAT deficiency face challenges to HRQL that are similar to older adults with chronic pulmonary disease. Further research is needed on the nature of the relationship between disease severity and HRQL in this population.

Radiation-induced signal transduction. Mechanisms and consequences.

Over a dose range up to 50 Gy of low-LET (linear energy transfer) ionizing radiation and up to 5 kJ/m2 UVB, mammalian cells convert molecular damage into productive response (mostly gain of function). By inactivation of negative regulatory components, such as protein tyrosine phosphatases as one mechanism discovered, the balance between restraining and stimulating influences is disturbed and an increase in signal flow results. Also DNA damage causing transcriptional arrest produces a signalling cascade of as yet unknown details. Such stimulation of the intracellular communication network can lead to apoptosis, elevated cell cycling and differentiation processes possibly including repair and recombination. The outcome likely depends on integration of all signals received which is as yet ill-understood. Although accurate determinations of low-dose inductions have not been achieved for technical reasons, the dose-response curves of induced signal transduction likely show threshold characteristics, in contrast to the direct consequences of DNA damage.

When is the dyspnea worth it? Understanding functional performance in people with alpha-1 antitrypsin deficiency.

OBJECTIVE AND SIGNIFICANCE: To examine functional performance in people with emphysema because of alpha-1 antitrypsin (AAT) deficiency. A severe deficiency of AAT affects 1:3,500 to 1:1,670 Americans who can develop debilitating emphysema in the third to fifth decades of life. DESIGN: Exploratory. POPULATION: People with a severe deficiency of AAT. SAMPLE AND DEMOGRAPHICS: Thirty-three patients (21 men) with a mean age of 47 (SD = 7) years. YEARS: Data were collected 1993-1996. METHODS: Activities patients identified as important on the dyspnea subscale of the Chronic Respiratory Disease Questionnaire were categorized and interpreted within the context of an integrity framework (i.e., effectiveness--or connectedness-related). FINDINGS: Patients identified over 25 activities. Effectiveness activities, such as bathing, were mentioned most frequently (78%). Connectedness activities, such as playing with children, were mentioned less often (22%) but were ranked more important. Two patients reviewed and supported the content validity of the framework. CONCLUSIONS: Results offer insight into the activities patients with genetic emphysema choose to perform and the factors that influence the decision that "the dyspnea is worth it." IMPLICATIONS: Identifying the activities people with AAT deficiency choose to perform and understanding why these activities are meaningful can guide interventions to help patients maintain a sense of integrity.

Synthesis and biological evaluation of aeroplysinin analogues: a new class of receptor tyrosine kinase inhibitors.

Receptor tyrosine kinases (RTKs), such as the epidermal growth factor receptor (EGFR) and the platelet-derived growth factor receptor (PDGFR), are critically involved in the transduction of mitogenic signals across the plasma membrane and therefore in the regulation of cell growth and proliferation. Enhanced RTK activity is associated with proliferative diseases such as cancer, psoriasis and atherosclerosis, while decreased function may be associated for instance with diabetes. EGFR and PDGFR are selectively inhibited by analogues of the marine natural product aeroplysinin. The synthetic inhibitors display IC50 values in the low micromolar range and in contrast to the natural product show pronounced inhibitory activity in cultured cells in vivo. The mechanism of inhibition is likely based on a covalent modification of the target enzymes by reaction of epoxy ketone 8 with various nucleophiles.

Clinical evaluation of noninvasive monitoring of oxygen saturation in critically ill patients.

OBJECTIVE: To examine the effect of abnormal cardiac index on the accuracy of measurement of oxygen saturation by pulse oximetry. METHODS: Forty-six patients (mean age, 49 years) in a 9-bed medical ICU were studied. Measurements of oxygen saturation obtained with pulse oximeters and with a functional cooximeter were collected at baseline and 4, 8, 16, 24, 32, 40, and 48 hours later. Hemodynamic and cardiopulmonary parameters were recorded. RESULTS: The Bland-Altman technique yielded upper and lower limits of agreement of 2.53% and -7.11%. Most (95.7%) of the differences between the measurements of oxygen saturation obtained with the 2 methods were within these limits, although some of these differences may be clinically unacceptable. The bias was -2.29%, and the precision was 2.41%. The clinical conditions associated with inaccurate tracking of saturation by pulse oximetry across the range of actual arterial oxygen saturation values were abnormal cardiac index, partial pressure of carbon dioxide, heart rate, and pulmonary capillary wedge pressure. CONCLUSIONS: In patients with abnormal cardiac index, the pulse oximeter measurements exceeded the actual oxygen saturation by up to 7%. Pending prospective studies, clinicians should be aware that when certain cardiopulmonary parameters are abnormal, the margin of error in measurements of oxygen saturation obtained with a pulse oximeter may be greater than when those parameters are normal.

Ligand-independent activation of platelet-derived growth factor receptor is a necessary intermediate in lysophosphatidic, acid-stimulated mitogenic activity in L cells.

Growth factor-derived mitogenic signals from the cell surface are transmitted to the nucleus via receptor tyrosine kinases (RTKs), the adaptor proteins Shc and Grb2, and a Ras-dependent protein kinase cascade that activates the extracellular signal regulated kinase (ERK) subfamily of mitogen-activated protein kinases. ERKs also are activated by hormones that stimulate G protein-coupled receptors (GPCRs). We report here that, in agreement with previous data, the epidermal growth factor receptor (EGFR) is a signaling intermediate in ERK activation by GPCRs. Of import, we show that cross-talk between two classes of surface receptors, RTKs and GPCRs, is a general feature. Lysophosphatidic acid not only induces ligand-independent tyrosine autophosphorylation of EGFR but also of platelet-derived growth factor beta receptor (PDGF-beta-R) as shown by detection of tyrosine phosphorylation and by the use of specific inhibitors of RTKs. The cross-talk appears to be cell type-specific: In L cells that lack EGFR, lysophosphatidic acid-induced Shc and ERK activation is prevented completely by specific inhibition of PDGFR, whereas in COS-7 cells expressing only EGFR, the pathway via EGFR is chosen. In Rat-1 cells, however, that express both EGFR and PDGFR, the EGFR pathway dominates.

Weaning from mechanical ventilatory support: refinement of a model.

The American Association of Critical-Care Nurses sponsored the third National Study Group to advance the science of weaning from mechanical ventilatory support and to guide clinical practice. The study group proposed a model of weaning in 1994 to provide an organizing framework for scientific inquiry. Since the model was first proposed, the ongoing work of the study group has led to refinement of the model. The purpose of this brief communication is to inform critical care clinicians and researchers about the refinements.